Transmission assembly with chain

The invention discloses a transmission assembly with a chain. The transmission assembly is provided with a chain group consisting of a plurality of chains, wherein one part of the chains in the chain group are singly arranged in a load path provided by the transmission assembly, and the other part of the chains are singly arranged in a backflow passage of a backflow assembly provided by the transmission assembly, while the chains need reversing in the backflow passage, therefore, when the chains in the backflow passage are assembled, firstly, the backflow assembly is combined to ensure that the backflow passage is an integral flow passage, then the chains are arranged in the passage from the end part of the backflow passage so that the chains can reverse along the path of the backflow passage; in addition, a rolling piece is remained by the integral backflow passage, therefore, the rolling piece cannot fall off. The technical scheme can greatly shorten the assembling time of the transmission assembly so as to